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arXiv · 2103.07229

Wehrl entropy, entropic uncertainty relations and entanglement

Stefan Floerchinger·Tobias Haas·Henrik Müller-Groeling
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Abstract

The Wehrl entropy is an entropy associated to the Husimi quasi-probability distribution. We discuss how it can be used to formulate entropic uncertainty relations and for a quantification of entanglement in continuous variables. We show that the Wehrl-Lieb inequality is closer to equality than the usual Bia{\l}ynicki-Birula and Mycielski entropic uncertainty relation almost everywhere. Furthermore, we show how a Wehrl mutual information can be used to obtain a measurable perfect witness for pure state bipartite entanglement, which additionally provides a lower bound on the entanglement entropy.

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Stefan Floerchinger, Tobias Haas, Henrik Müller-Groeling. 2021-03-12. Wehrl entropy, entropic uncertainty relations and entanglement. https://doi.org/10.1103/physreva.103.062222

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